Final answer:
The herb associated with decreasing memory loss in aging is Ginkgo biloba, but conclusive evidence for its effectiveness is lacking. Abscisic acid is the hormone that, when decreased, releases seeds from dormancy.
Step-by-step explanation:
The herb that is thought to decrease memory loss associated with aging is c. Ginkgo biloba. Ginkgo biloba leaves are sometimes used in herbal medicine with the belief that they can improve brain function. However, it is important to note that conclusive evidence supporting the effectiveness of Ginkgo biloba in enhancing memory or cognitive functions is lacking.
Regarding the second part of the question, a decrease in the level of a. abscisic acid is known to release seeds from dormancy. Abscisic acid is a plant hormone that inhibits growth and promotes seed dormancy, while its decrease can facilitate the germination process.